Not Applicable
Not Applicable
This invention relates to a surface milling or angular milling cutter.
DE 197 06 377 has made known a surface milling or angular milling cutter wherein a carrier body circumferentially has disposed pockets which extend in parallel with the axis of rotation of the carrier body and serve for the accommodation of cassettes. The cassettes, in turn, exhibit seating surfaces for the accommodation of tool tips. The tool tips are mounted in the cassette by means of a suitable fixing device, e.g. by means of bolts which are passed through a through bore of the tool tips. The cassettes, in turn, are adapted to be mounted in the pockets, e.g. also by means of a bolt which interacts with a threaded bore in the bottom of the pocket. In the known tool, means are further provided to axially adjust the cassette in order that sufficient planarity is obtained for the entirety of the tool tips. In an embodiment, a single adjusting bolt is provided for each cassette which is seated in a threaded bore of the carrier body which extends, starting from the front-end face of the carrier body, approximately in parallel with the axis of rotation of the carrier body. For example, the adjusting bolt has a head which interacts with a matching recess of the cassette. Thus, the cassette may actively be set in a precise way in the two axial directions. Rough setting is performed by the mounting of the cassette in the pocket. Therefore, precise setting can only be effected within the range of the cassette mounting tolerance.
In another embodiment of the known surface milling and angular milling cutter, it is known to accommodate the cassettes in the pockets in a snug fit and to provide the carrier body with a radial stop surface directed to the free front-end face of the carrier body to enable the cassettes to abut thereon. Then, the cassettes may be caused to abut on the stop surface by means of the adjusting pin.
Even following such adjustment, undesirable deviations of the position of the cutting inserts may still occur on the surface milling and angular milling cutter, especially by the fact that the cassettes are finally tightened. The cutting inserts frequently consist of a hard material or are coated with a hard material or diamond, which cutting material reacts very sensitively to excessively strong stresses which unquestionably occur if the cutting inserts deviate from the surface plane.
Therefore, the object of the invention is to provide a surface milling or angular milling cutter by which highly precise surfaces may be shaped on the workpiece.
In the invention, the cassette has included, in a radially outwardly disposed portion, a gap extending approximately in the radial plane of the carrier body which thus divides the radially outward portion of the cassette into two axially spaced-apart subportions. The gap receives a setting wedge which is adapted to be radially displaced by means of an adjusting screw in the gap. If a maladjustment is found to exist after the final tightening of the cassette, which has been preceded already by an adjustment of the cassette in the pocket, either by means of the adjusting screw which is axially displaceable in the two directions or by causing the cassette to abut on a stop surface, re-adjustment can be made by means of the setting wedge.
The displacement of the setting wedge in the gap is preferably performed by means of a bolt which is passed through a through bore of the wedge and interacts with a threaded bore in the bottom of the gap. The gap may also wedge-shaped here.
Since a certain volume of material is necessary for the wedge to enable a through bore for the adjusting screw and provide stability one aspect of the invention provides that a groove which receives a complementary rib of the wedge is formed in one wall of the gap, preferably the one which faces away from the cutting insert. The groove and the wedge preferably are semicircular in cross-section. Then, the through bore may be passed, in part, through the rib of the wedge. Thus, sufficient material may be maintained between the seating surfaces for the cutting insert and the gap. This is particular important if the cutting insert is mounted in the cassette by means of an approximately central bolt.
Since the cutting insert normally is not mounted centrally with regard to the longitudinal axis of the cassette it is advantageous, according to another aspect of the invention, if the wedge, which is of the width of the cutting insert at the most, is disposed in a relationship directly facing the cutting insert in the gap. This enables the wedge to efficiently transmit the axial force exerted onto the cutting insert.
The invention will now be explained in greater detail with reference to an embodiment shown in the drawings.